Zip Code | City | Population |
|---|---|---|
| 03820 | Dover | 32,925 |
| 03867 | Rochester | 22,349 |
| 03824 | Durham | 15,073 |
| 03878 | Somersworth | 12,088 |
| 03825 | Barrington | 9,339 |
| 03835 | Farmington | 6,777 |
| 03868 | Rochester | 6,368 |
| 03861 | Lee | 4,547 |
| 03884 | Strafford | 4,261 |
| 03851 | Milton | 4,195 |
| 03839 | Rochester | 3,856 |
| 03855 | New Durham | 2,711 |
| 03869 | Rollinsford | 2,427 |
| 03823 | Madbury | 2,213 |
| 03887 | Union | 1,954 |
| 03852 | Milton Mills | 314 |